CN207725390U - A kind of exhaust apparatus of braking system of electric car - Google Patents

Abstract

The utility model discloses an exhaust device for a brake system of an electric vehicle, which comprises a control device, a vacuum pump, a liquid storage chamber, and a detection cylinder body with a detection chamber. The first and second electromagnetic valves are respectively arranged on the pipelines connecting the vacuum pump, the liquid storage chamber and the detection chamber. One end of the detection chamber is connected to one end of the exhaust pipe with the third electromagnetic valve. The other end is provided with a pressurized plunger, and the pressurized plunger is associated with a driving device driven by a motor. The other end of the exhaust pipe is provided with a connector that can be connected with the installation hole of the air release screw of the brake system. The chamber and the detection chamber are connected through an over-extraction pipe provided with a fourth electromagnetic valve, and hydraulic pressure sensors are respectively provided on the air-extraction pipe and the detection chamber. The utility model can realize single-person operation, thereby improving the efficiency, and can accurately control the exhaust program to ensure thorough exhaust and avoid excessive exhaust.

Description

Exhaust device for braking system of electric vehicle

technical field

The utility model relates to the technical field of electric vehicle manufacturing, in particular to an exhaust device for a braking system of an electric vehicle.

Background technique

The braking system of an electric vehicle is usually a brake fluid tank that is filled with brake fluid, a brake master cylinder, a front brake wheel cylinder that controls the front brakes, a rear brake wheel cylinder that controls the rear brakes, a A closed system consisting of hydraulic regulators for hydraulic fluid, brake lines connected between the two components, and other components. When working, the basically incompressible brake fluid moves in the circuit of the system, stepping on the brake pedal, and through the boosting effect of the vacuum booster, the brake master cylinder pushes the brake fluid to move in the circuit, and then pushes the front brake The moving wheel cylinder and the rear brake wheel cylinder move, and the front and rear brakes work to generate braking torque. We know that air has compressible characteristics, so once there is air in the closed circuit system of the brake system, the air in the circuit will be compressed first when braking, and then the brake fluid can be pushed to move, which will Cause the loss of the brake pedal travel, thereby increasing the braking reaction time, and reducing the output of the braking force, resulting in serious safety hazards.

For this reason, according to the situation of actual test, people set corresponding air-relieving screw in suitable position in the closed braking circuit. When the brake pedal is stepped on for many times, the air in the circuit will gradually flow and gather at the position where the air release screw is set. At this time, the air release screw can be opened to release the gas mixed with the brake fluid.

In the prior art, people will discharge the air in the closed circuit of the braking system to the outside through various methods, and the most commonly used method is to cooperate with two operators, one of whom is constantly stepping on the brake pedal in the cab. move the pedal so that the air in the circuit gathers together and moves to the place where the bleed screw is set, then keep the brake pedal depressed and the brake circuit maintains a high pressure state, and another person releases the air in the brake circuit under the vehicle body When the air screw is opened, the air mixed with the brake fluid in the brake circuit will be discharged to form air bubbles. The degassing procedure can be completed when there are no more air bubbles to be observed by the naked eye. Although this method does not require a special device, it has the following defects: on the one hand, it needs two people to cooperate with the operation, so its efficiency is low; on the other hand, the brake fluid is corrosive, so it will cause adverse effects on the health of operators influences. In particular, this method requires the operator to have rich experience, and the two persons should cooperate well, otherwise, the problem of incomplete exhaust or excessive exhaust will easily occur.

A kind of "exhaust device of vehicle brake system" is disclosed in the Chinese patent literature, and its announcement number is CN203047242U. The vehicle brake system includes a brake cylinder with an oil discharge port; the exhaust device includes a transparent air pump. A manual control switch and a suction pipe are connected in series in the start-stop control circuit of the suction pump. The suction pipe has a first end connected to the inlet side of the suction pump and a second end for connecting to an oil drain. When exhausting, start the air extraction pump, observe the situation in the transparent air extraction pipe, if the brake fluid has flowed out, it means that the exhaust is completed, and the air extraction pump can be turned off.

However, the above-mentioned exhaust device still has the following defects: First, the exhaust gas through the exhaust device still needs two people to cooperate, in other words, it needs to be stepped on the brake pedal repeatedly by one person, so that the air in the brake circuit is accumulated Go to the deflation screw, and another person observes the condition of the exhaust pipe. Secondly, it is difficult for the operator to accurately determine the exhaust status by observing the condition of the exhaust pipe, and the problem of incomplete exhaust or excessive exhaust is likely to occur.

Utility model content

The purpose of this utility model is to solve the problems of low efficiency and difficult to control accurately in the existing exhaust device of the braking system of electric vehicles, and to provide an exhaust device of the braking system of electric vehicles, which can realize a single Human operation is required to improve efficiency, and the exhaust program can be accurately controlled to ensure thorough exhaust and avoid excessive exhaust.

In order to achieve the above object, the utility model adopts the following technical solutions:

An exhaust device for an electric vehicle braking system, comprising a control device, a vacuum pump, a liquid storage chamber, and a detection cylinder with a cylindrical detection chamber, the suction port of the vacuum pump passes through pipelines and the liquid storage chamber, The detection chamber of the detection cylinder is connected. A first solenoid valve is provided on the pipeline connecting the vacuum pump and the liquid storage chamber, and a second solenoid valve is provided on the pipeline connecting the vacuum pump and the detection chamber. The detection chamber in the detection cylinder One end of one end is connected with one end of an air extraction pipe, a third solenoid valve is provided on the air extraction pipe, and a pressurized plunger is provided at the other end of the detection chamber, and the pressurized plunger is associated with a driving device driven by a motor, The other end of the air extraction pipe is provided with a connector that can be connected to the installation hole of the air release screw of the brake system. The liquid storage chamber and the detection chamber are connected through the liquid extraction pipe, and a fourth The solenoid valve, the pumping pipe and the detection chamber are respectively provided with hydraulic sensors, and the control device is electrically connected with the vacuum pump, the motor of the driving device and the first, second, third and fourth solenoid valves.

When exhaust is needed, we can first remove the deflation screw of the braking system of the electric vehicle, and then connect the exhaust device of the present utility model to the mounting hole for installing the deflation screw through the connector on the exhaust pipe. The operator can step on the brake pedal repeatedly to make the air in the brake circuit gather at the installation hole of the air release screw, and at this time, the brake fluid in the brake circuit maintains a relatively high pressure. Then the operator can start the exhaust device, the control device first opens the second electromagnetic valve and starts the vacuum pump to form a negative pressure in the detection chamber, and then opens the third electromagnetic valve, and the brake circuit has a high pressure mixed with brake fluid. Air enters through the suction pipe and fills the detection chamber. Then the control device closes the third solenoid valve, and moves the pressurizing plunger through the driving device, thereby applying pressure to the gas-liquid mixture in the detection chamber.

We know that when the air in the brake circuit enters the detection chamber, there will be a small amount of brake oil at the beginning, and then the brake oil that is drawn out will gradually increase. When all the air is exhausted, all the brake oil that enters the detection chamber fluid. Because the brake fluid is basically incompressible, and the air can form a great amount of compression, therefore, when the drive device operates for a set time and ends, the pressurized plunger moves a fixed distance, and the detection chamber Then a fixed compression amount is formed, and the control device can make a judgment according to the pressure signal output by the hydraulic pressure sensor on the detection chamber: if the pressure in the detection chamber is high, it means that the proportion of air in the detection chamber is low, and the brake The proportion of fluid is relatively high, that is to say, the air in the brake circuit has been expelled, and a sufficient amount of brake fluid has been pumped into the detection chamber, so that the control device can stop the exhaust process. Conversely, if the pressure in the detection chamber is low, it means that the proportion of air in the detection chamber is relatively high, while the proportion of brake fluid is low, that is to say, only a small amount of brake fluid mixed in the air is pumped out. Into the detection chamber, but the air in the brake circuit has not been completely discharged, so the control device can repeat the exhaust procedure again until the air in the brake circuit is completely discharged. It should be noted that the utility model creatively uses the pressure of a detection chamber as the basis for judging whether the exhaust is sufficient, which can effectively avoid insufficient exhaust or excessive exhaust caused by human factors of the operator. In particular, the operator in the cab does not need to leave the cab to observe the exhaust state, the exhaust device itself can make accurate judgments, so as to realize the single-person operation of the exhaust and significantly improve the efficiency of the exhaust. It can be understood that we can obtain a maximum pressure value of the detection chamber for judging whether the exhaust is sufficient when the pressurized plunger is pressurized according to the experimental results, so as to accurately determine the exhaust state.

When the exhaust procedure ends, the control device can open the first solenoid valve and the fourth solenoid valve, so that a negative pressure is formed in the liquid storage chamber, so that the high-pressure brake fluid in the detection chamber flows into the liquid storage chamber through the suction pipe , so as to facilitate the next exhaust procedure.

Preferably, the driving device includes an outer casing connected to the pressurizing plunger, a driving screw is threaded inside the outer casing, and the driving screw is coaxially connected with the output shaft of the motor.

When the motor drives the driving screw to rotate, it can drive the outer casing threadedly connected with it to reciprocate in the axial direction, and then drive the pressurizing plunger to move. Since the thread fit has a labor-saving effect similar to that of a worm gear, it can significantly reduce the torque required by the electrode and reduce the rated power of the motor.

As a preference, a liquid return pipe extending into the bottom of the liquid storage chamber is vertically provided on the top of the liquid storage chamber, the detection chamber is vertically arranged in a cylindrical shape, the inner side wall of the lower end of the detection chamber is conical, and the pumping One end of the liquid pipe is connected to the center of the lower end of the detection cylinder, the other end of the suction pipe is connected to the upper end of the liquid return pipe, the lower end of the liquid return pipe is provided with a check valve, and the suction pipe is connected to the side of the detection cylinder on the wall.

In the utility model, a liquid return pipe inserted to the bottom is arranged in the liquid storage chamber, so that when the vacuum pump makes the liquid storage chamber form a negative pressure, the brake fluid entering the liquid storage chamber from the liquid suction pipe can be prevented from being sucked out by the vacuum pump. The air in the mixture of brake fluid and air entering the liquid storage chamber through the liquid return pipe will be quickly released to the upper space of the liquid storage chamber under the action of negative pressure in the liquid storage chamber, so as to achieve good gas-liquid separation . The check valve can prevent the brake fluid in the liquid storage chamber from flowing back into the detection chamber through the liquid suction pipe. In particular, the detection chamber of the present utility model is a vertical cylinder, and the lower end of the detection chamber is conical, so the brake fluid in the detection chamber will automatically be stored at the lower end of the detection chamber, and through the The suction pipe at the center of the lower end of the detection cylinder flows into the liquid storage chamber to avoid the formation of brake fluid residue in the detection chamber.

Therefore, the utility model has the following beneficial effects: single-person operation can be realized, thereby improving efficiency, and the exhaust program can be accurately controlled to ensure thorough exhaust and avoid excessive exhaust.

Description of drawings

Fig. 1 is a kind of structural representation of the utility model.

In the figure: 1. Vacuum pump 2, liquid storage chamber 21, liquid return pipe 22, check valve 3, detection cylinder 31, detection chamber 32, pressurizing plunger 40, first solenoid valve 41, second solenoid valve 42, The third electromagnetic valve 43, the fourth electromagnetic valve 5, the motor 51, the driving screw 52, the outer casing 6, the air extraction pipe 61, the connector 7, and the liquid extraction pipe.

Detailed ways

The utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, an exhaust device for an electric vehicle braking system includes a control device with a logic controller, a vacuum pump 1, a liquid storage chamber 2, and a cylindrical detection cylinder 3, and the detection cylinder has a cylinder In the body-shaped detection chamber 31, one suction port of the vacuum pump communicates with the liquid storage chamber through a pipeline, and the other suction port of the vacuum pump communicates with the side of the detection chamber of the detection cylinder through a pipeline. Set a first electromagnetic valve 40 on the pipeline connecting the vacuum pump and the liquid storage chamber to control the on-off of the pipeline; set a second electromagnetic valve 41 on the pipeline connecting the vacuum pump and the detection chamber to control the on-off of the pipeline .

In addition, a pressurized plunger 32 is set in the detection chamber at one end of the detection cylinder, and the pressurized plunger is associated with a driving device whose power source is a motor 5, so that the control device can drive The motor of the device controls the left and right movement of the pressurized plunger. The side of the other end of the detection cylinder away from the pressurized plunger is provided with a suction pipe 6 connected to the detection chamber, and the other end of the suction pipe is provided with a connector 61 that can be connected to the mounting hole of the air release screw of the braking system. A third electromagnetic valve 42 which can be controlled to be switched on or off is arranged on the exhaust pipe.

In addition, the liquid storage chamber and the detection chamber are connected through a liquid suction pipe 7, and a fourth electromagnetic valve 43 that can be controlled to be turned on and off is arranged on the liquid suction pipe. Of course, we also need to set hydraulic sensors capable of sensing internal pressure on the exhaust pipe and the detection chamber, and the control device is electrically connected to the vacuum pump, the motor of the drive device, and the first, second, third, and fourth solenoid valves, and A start switch is arranged on the control device.

When exhaust is needed, we can first remove the bleed screw of the electric vehicle brake system, and then connect the connector on the exhaust pipe to the mounting hole used to install the bleed screw. At this time, the operator can step on the brake repeatedly. Pedal, so that the air in the brake circuit accumulates to the installation hole of the bleed screw, and continue to step on the brake pedal for about 30 seconds. At this time, the brake fluid in the brake circuit maintains a relatively high pressure. Then the operator can press the start switch on the control device, the control device first opens the second solenoid valve and starts the vacuum pump, and closes the second solenoid valve when the vacuum pump makes enough negative pressure in the detection chamber. Then open the third electromagnetic valve, the air with high pressure mixed with the brake fluid in the brake circuit enters through the exhaust pipe and fills the detection chamber, and then the control device closes the third electromagnetic valve to keep the detection chamber closed. Then the control device moves the pressurizing plunger to the left by a set distance through the driving device, so as to pressurize the gas-liquid mixture in the detection chamber. At this time, the hydraulic pressure sensor on the detection chamber outputs a pressure signal to the control device, and at the same time opens the first solenoid valve and the fourth solenoid valve to form a negative pressure in the liquid storage chamber, thereby relying on the pressure difference between the detection chamber and the liquid storage chamber to open the detection chamber. The brake fluid inside is pumped into the reservoir chamber. If the pressure in the detection chamber output by the hydraulic sensor reaches the preset value, it means that the proportion of brake fluid in the detection chamber is relatively high, and the control device determines that the exhaust is sufficient and ends the exhaust procedure; If the pressure does not reach the pre-set value, it means that the proportion of brake fluid in the detection chamber is relatively low, then the control device determines that the exhaust is insufficient and restarts the exhaust procedure.

In order to facilitate the control of the movement of the pressurized plunger, the driving device of the present invention includes a motor 5, the output shaft of the motor is coaxially connected with a driving screw 51, and one end of the pressurized plunger is connected to an outer casing 52. Connected, the outer casing protrudes outward from the end of the detection cylinder, and the driving screw is threaded in the outer casing. In this way, when the motor drives the driving screw to rotate, it can drive the outer casing threaded with it to move reciprocally in the axial direction, and then drive the pressurizing plunger to move.

It should be noted that the motor can be a stepper motor, so as to accurately control the moving distance of the pressurizing plunger. And the shape of the outer casing can be a square or a regular hexagon, so as to prevent the outer casing from rotating together with the driving screw.

Furthermore, we can vertically set a liquid return pipe 21 extending into the bottom of the liquid storage chamber on the top of the liquid storage chamber, and make the detection cylinder vertically arranged, and the inner wall of the lower end of the detection chamber is conical. One end of the liquid suction pipe is connected to the center of the lower end of the detection cylinder, the other end of the liquid suction pipe is connected to the upper end of the liquid return pipe, and a check valve 22 is installed at the lower end of the liquid return pipe, while the pipeline connected to the vacuum pump is connected to in the upper part of the reservoir.

In this way, when the vacuum pump makes the liquid storage chamber form a negative pressure, the brake fluid entering the liquid storage chamber from the liquid suction pipe can be prevented from being sucked out by the vacuum pump. The air in the mixture of brake fluid and air entering the liquid storage chamber through the liquid return pipe will be quickly released to the upper space of the liquid storage chamber under the action of negative pressure in the liquid storage chamber, so as to achieve good gas-liquid separation . The check valve can prevent the brake fluid in the liquid storage chamber from flowing back into the detection chamber through the liquid suction pipe.

Claims (3)

1. An exhaust device for an electric vehicle braking system, comprising a control device, a vacuum pump, a liquid storage chamber, and a detection cylinder with a columnar detection chamber, wherein the suction port of the vacuum pump passes through the pipe respectively The pipeline is connected with the liquid storage chamber and the detection chamber of the detection cylinder. A first solenoid valve is provided on the pipeline connecting the vacuum pump and the liquid storage chamber, and a second solenoid valve is provided on the pipeline connecting the vacuum pump and the detection chamber. One end of the detection chamber in the detection cylinder is connected with one end of an air extraction pipe, and a third solenoid valve is provided on the air extraction pipe, and a pressurized plunger is provided at the other end of the detection chamber, and the pressurized plunger is connected with a motor-driven The other end of the air extraction pipe is provided with a connector that can be connected to the installation hole of the air release screw of the brake system. The liquid storage chamber and the detection chamber are connected through the liquid suction pipe. A fourth solenoid valve is provided on the pipe, hydraulic sensors are respectively provided on the pumping pipe and the detection chamber, and the control device is electrically connected to the vacuum pump, the motor of the drive device, and the first, second, third, and fourth solenoid valves. . 2. The exhaust device of a braking system of an electric vehicle according to claim 1, wherein the driving device comprises an outer casing connected to the pressurizing plunger, and a driving screw is threaded inside the outer casing, The drive screw is coaxially connected with the output shaft of the motor. 3. The exhaust device of a braking system of an electric vehicle according to claim 1, wherein a liquid return pipe extending into the bottom of the liquid storage chamber is vertically provided on the top of the liquid storage chamber, and the detection The chamber is vertically arranged in a cylindrical shape, the inner side wall of the lower end of the detection chamber is conical, one end of the liquid suction pipe is connected to the center of the lower end of the detection cylinder, and the other end of the liquid suction pipe is connected to the upper end of the liquid return pipe, A check valve is provided at the lower end of the liquid return pipe, and the air extraction pipe is connected to the side wall of the detection cylinder.